I cannot speak for the EX, but, when the fan is on and the recirculate button is not depressed, that is outside air that is being circulated, whether the AC is on or off. To verify this, you only have to tuck in behind an old smog spewing junker or a diesel schoolbus (never did understand why they are allowed to have the low level exhaust, which pipes the fumes right into a car's air intake).
Jerry O.
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2001 Odyssey GG LX
Jerry O.
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2001 Odyssey GG LX